[rgoulter]

Nix is good at solving more problems than containers can solve. Nix is good at "programmatically managing packages".

For just the problem of "I want to be able to distribute the same application everywhere", container images solve this well. This can also be solved using Nix instead of container images; or Nix can even be used to build the container images.

The Nix expression language is much more expressive/powerful/elegant than Dockerfile's syntax is. -- Which can be useful for stuff like declaring "I want <program> built with different build flags / patches".

Nix ends up being useful for scratching the itch of "put in effort now, to save effort later".